What is it that draws thousands of young Europeans to jihadism and violence? What is it that has led 4,000 to travel to Syria to fight for the so-called Islamic State (ISIS)? And what is it that leads European citizens to engage in barbarous carnage such as those witnessed last month in Paris?

The conventional answer is that they have become "radicalized," a process through which vulnerable Muslims are groomed for extremist violence by those who champion hate. The radicalization argument consists of four broad elements. The first is the claim that people become terrorists because they acquire certain, usually religiously informed, extremist ideas. The second is that these ideas are acquired in a different way from that in which people acquire other extremist or oppositional ideas. The third is that there is a conveyor belt that leads from grievance to religiosity to the adoption of radical beliefs to terrorism. And the fourth is the insistence that what makes people vulnerable to acquiring such ideas is that they are poorly integrated into society.

The trouble is that these assumptions, which underlie much of Europe's domestic counterterrorism policy, are wrong.

Many studies show, for instance, that those who are drawn to jihadist groups are not necessarily attracted by fundamentalist religious ideas. A 2008 study by Britain's MI5 on extremism that was leaked to the press observed that "far from being religious zealots, a large number of those involved in terrorism do not practice their faith regularly."

There is also little evidence that jihadists acquire their ideas differently from other kinds of groups, even though conventional wisdom suggests that their ideology comes from hate preachers and the like, whereas other radical ideas are born of different circumstances. Jamie Bartlett, head of the Violence and Extremism program at the British think tank Demos, argues that such terrorism "shares much in common with other counter-cultural, subversive groups of predominantly angry young men."

Nor is there any evidence of a straight path leading people from radical ideas to jihadist violence. A 2010 British government report concluded that the conveyor belt thesis "seems to both misread the radicalization process and to give undue weight to ideological factors."

And finally, there is much evidence that those who join jihadi groups are anything but poorly integrated, at least in the conventional sense of integration. A survey of British jihadists by researchers at Queen Mary College in London found that support for jihadism is unrelated to social inequality or poor education; rather, those drawn to jihadist groups were 18- to 20-year-olds from wealthy families who spoke English at home and were educated to a high, often university, level. In fact, "youth, wealth, and being in education," as the study put it, "were risk factors."

In a sense, the radicalization argument looks at the jihadists' journey from back to front. It begins with the jihadists as they are at the end of their journey—enraged about the West, and with a black-and-white view of Islam—and assumes that these are the reasons they have come to be as they are. What draws young people (and the majority of would-be jihadis are in their teens or twenties) to jihadi violence is a search for something a lot less definable: for identity, for meaning, for belongingness, for respect. Insofar as they are alienated, it is not because wannabe jihadis are poorly integrated, in the sense of not speaking the local language or being unaware of local customs or having little interaction with others in the society. Theirs is a much more existential form of alienation.

Charles Platiau / ReutersA young Muslim girl has two French flags and a headband which reads " Fraternity" on her headscarf as she march among about 3,000 Sikhs from across Europe protesting on a Paris boulevard to defend their traditional headgear against a looming French ban on religious symbols in state schools, January 31, 2004.

ANGSTY

There is, of course, nothing new in expressions of alienation and angst. The youthful search for identity and meaning is cliché. What is different today is the social context in which such alienation and searching occurs. We live in an age of growing social disintegration, in which many people feel peculiarly disengaged from mainstream social institutions.

The real starting point for the making of a homegrown jihadist is not radicalization but this kind of social disconnection, a sense of estrangement from, resentment of, Western society. It is because they have already rejected mainstream culture, ideas, and norms that some Muslims search for an alternative vision of the world. It is not surprising that many wannabe jihadis are either converts to Islam, or Muslims who discovered their faith only relatively late. In both cases, disenchantment with what else is on offer has led them to the black-and-white moral code of extremist Islamism. It is not, in other words, a question of being "groomed" or "indoctrinated" but of losing faith in mainstream moral frameworks and searching for an alternative.

Disengagement is, of course, not simply a Muslim issue. There is today widespread disenchantment with the political process, a sense of being politically voiceless, a despair that neither mainstream political parties nor social institutions such as the church or trade unions seem to comprehend their concerns and needs.

All this has inevitably shaped how young people, and not just those of Muslim backgrounds, experience their alienation, and how they are able to act upon it. In the past, such disaffection with the mainstream may have led people, certainly in Europe, to join movements for political change, from far-left groups to labor movement organizations to anti-racist campaigns. Such organizations gave idealism and social grievance a political form, and a mechanism for turning disaffection into social change.

Today, such campaigns and organizations can seem as out-of-touch as mainstream institutions. In part, this is because the broad ideological divides that had characterized politics for much of the past two hundred years have been all but erased. Distinctions between left and right have become less meaningful. The weakening of labor organizations and other institutions, the decline of collectivist ideologies, the expansion of the market into many nooks and crannies of life—all have helped create a more socially, fragmented society.

In turn, identity politics has become more salient; fragmentation has encouraged people to define themselves in increasingly narrow ethnic or cultural terms. Public policies aimed at integrating minorities have only helped exacerbate this process. After the Paris attacks, many commentators insisted that at least part of the blame must lie with French "assimilationist" social policies which, they claimed, had failed to integrate Muslims and had created a more divided society. Social policies that took more account of the diversity of French society, they suggested, would have better served France.

Michael Dalder / Reuters

A member of BAGIDA, the Bavarian section of the anti-immigration movement Patriotic Europeans Against the Islamisation of the West (PEGIDA), holds a poster depicting German Chancellor Angela Merkel during a march in the center of Munich, January 19, 2015. The text reads 'Mommy multicultural. Merkel's migration policy.'

Others responded that it made little sense to blame French social policies. Belgium, and in particular the Brussels area of Molenbeek, has become a nursery for jihadists even though Belgian social policy is more multicultural than assimilationist. Nor does pointing the finger at French social policy explain the roots of homegrown jihadism in the United Kingdom. It was in London that Europe's first suicide bombers killed 52 people on the 2005 attacks on the city's transport system. Three of the four bombers were born in in the United Kingdom; the other had been raised there since childhood.

The debate over assimilation versus multiculturalism is not new. For much of the past two decades, French politicians and policymakers had condemned Britain for its multicultural approach, warning that such policies were divisive and failed to create a common set of values or sense of nationhood. As a result, they argued, many Muslims were drawn to Islamism and violence. Now, many of the same arguments have been applied to French social policies.

PROBLEM POLICIES

Both sides are, to a degree, correct; French social policies are problematic, and have helped create a more divisive society. But, so have multicultural policies. For too long, politicians and policy makers have debated the differences between the two approaches but ignored the similarities.

British policymakers envisaged their nation as "a community of communities," in the words of the influential Parekh report on multiculturalism, published in 2000. But in doing so, they tended to treat minority communities as if each were a distinct, singular, homogenous, and authentic whole, composed of people speaking with a single voice and view of culture and faith. In other words, policymakers accepted that the United Kingdom was a diverse society, but they sought to manage that diversity by putting people into ethnic and cultural boxes, which where then used to define the needs and rights of those in them. They frequently accepted the most conservative, often religious, figures as the authentic voices of minority groups. Instead of engaging directly with Muslim communities, British authorities effectively delegated responsibility to so-called community leaders.

The consequence has been yet more fragmentation and a more parochial vision of Islam. It is not surprising, then, that most of those drawn toward jihadism are as estranged from Muslim communities as they are from Western societies. Most detest the mores and traditions of their parents and have little time for mainstream, government-sanctioned forms of Islam. Some are led to Islamism, which appears to provide a sense identity that they find neither in mainstream society nor in mainstream Islam. At the fringes, disaffection has become channeled into jihadism. Shaped by black-and-white ideas and values, a few have been drawn to commit acts of horror and to view such acts as part of an existential struggle between Islam and the West.

A cow runs stands in a meadow next to a display advertising the initiative against the construction of new minarets in Switzerland, November 13, 2009. Dario Bianchi / Reuters

The irony is that French social policies, which start from a very different point, have ended up creating many of the same problems. France is home to some five million or so French citizens of North African origin. Just 40 percent think of themselves as observant Muslims, and only one in four attend Friday prayers. Yet French politicians, intellectuals, and journalists look at them all as Muslims. Indeed, government ministers, academics, and journalists often cite France's "five million Muslims." The fashion for calling North Africans "Muslim" is relatively recent. In the 1960s and 1970s they may have been labeled beur or arabe (meaning someone from North Africa and Arab, respectively), but rarely Muslim. North African migrants certainly did not define themselves as Muslim; they were mainly secular, often hostile to religion.

The shift toward linking North Africans to Islam is a result of both the greater fracturing of French politics in recent years and the growing perception of Islam as an existential threat to the French republican tradition. French politicians, like those throughout Europe, have faced a public increasingly distrustful of and disengaged from mainstream institutions. And, like those in many European nations, they have attempted to assuage such hostility and resentment by reasserting the notion of a common French identity. Often finding it difficult to articulate clearly the ideas and values that characterize the nation, however, they have instead slipped into defining who the French arenot rather than who they are. In this case, Islam is the "other" against which French identity is defined.

"What, in today's France," asks the filmmaker and novelist Karim Miské, "unites the pious Algerian retired worker, the atheist French-Mauritanian director that I am, the Fulani Sufi bank employee from Mantes-la-Jolie, the social worker from Burgundy who has converted to Islam, and the agnostic male nurse who has never set foot in his grandparents' home in Oujda? What brings us together if not the fact that we live within a society which thinks of us as Muslims?"

In principle, the French authorities rejected the United Kingdom's multiculturalist approach. In practice, however, they treated North African migrants and their descendants in a very "multicultural" way—as a single community living alongside another.

The irony is that France's North African population is predominantly secular, and even practicing Muslims are relatively liberal in their views. According to 2011 study by the Institut Français d'Opinion Publique (IFOP), 68 percent of observant women never wear the hijab. Less than a third of practicing Muslims would forbid their daughters from marrying a non-Muslim. Eighty-one percent accept that women should have equal rights in divorce, 44 percent have no problem with cohabitation, 38 percent support the right to abortion, and 31 percent approve of sex before marriage. Homosexuality is the only issue on which there is a majority conservative stance: 77 percent of practicing Muslims disapprove.

Many in the second generation of North African communities are, just like their counterparts in Britain or Belgium, as estranged from their parents' cultures and mores, and from mainstream Islam, as they are from wider French society. And some, as elsewhere in Europe, find their way, to a darker, starker, more tribal vision of Islam. Consider, for instance, Cherif Kouachi, who masterminded the Charlie Hebdo slaughter in Paris in January. He was raised in Gennevilliers, a northern suburb of Paris, home to around 10,000 people of North African origin. He only rarely attended mosque, and appeared not to be particularly religious, but was driven by a sense of social estrangement. He was, according to Mohammed Benali, president of the local mosque, of a "generation that felt excluded, discriminated against, and most of all, humiliated. They spoke and felt French, but were regarded as Arabic; they were culturally confused."

FRACTURED SOCIETIES

Kouachi's story is not that different from that of Mohammad Sidique Khan, the leader of the 7/7 bombings in London. Nor is that different from the story of Abdelhamid Abaaoud, the mastermind of the Paris attacks. Abaaoud grew up in Molenbeek, the Brussels ghetto that has become a byword for poverty, unemployment, and radical Islamism. Abaaoud attended, however, one of Belgium's top secondary schools, Saint-Pierre d'Uccle. He dropped out of school and stopped visiting the local mosque, as did his close friend Salah Abdeslam, another of the Paris gunmen. The imams were too steeped in tradition for their tastes. "So they look elsewhere," says Olivier Vanderhaegen, who works in a local project to combat youth radicalization.

Social policies in Belgium, France, and the United Kingdom aimed at fostering integration are all different. What they have in common, though, is that all have helped create a more fractured society, and all have helped entrench narrower visions of belongingness and identity. Neither assimilationist nor multicultural policies have created Islamism or jihadism. What they have done is helped create the space for Islamism to flourish, and to funnel disaffection into jihadism.